Is there a Homosexuality Gene?

Shamelessly Quoted from: http://www.physorg.com/news84720662.html

Is there a homosexuality gene? Discussion at PhysOrgForum

Although biologists are still far from answering this question, scattered evidence for a possible gene influencing sexual orientation has recently encouraged scientists to map out a guide to future research. Because many possibilities for such a gene exist, scientists Sergey Gavrilets and William Rice have recently developed some theoretical guidelines and testable predictions for explaining the evolutionary causes of homosexuality.

“During the 1990s there was a short surge of interest by a small number of labs in finding major genes that might mediate homosexuality,” Rice told PhysOrg.com. “However, for a variety of reasons, this effort waned by the turn of the century. I think that—when studying humans—many people shy away from studying sexual phenotypes in general and homosexuality in particular. Much of Sergey's and my motivation in writing our paper was to rekindle an interest in studying the genetic basis of homosexuality. I personally think that if a firm genetic foundation for homosexuality in humans were established, then many people would view this fascinating human phenotype more objectively.”

During the past several decades, scientists have discovered some interesting patterns that may point toward genetic causes of homosexuality. Among the findings is that male homosexuality appears to be inherited more often from the mother than the father (Pillard). Also, natural selection might maintain a gene that may decrease the fecundity of one sex because the same gene also increases the fecundity of the other sex. In fact, recent data shows that female maternal relatives of gay men have higher than average reproduction capacity (Camperio-Ciani).

Another interesting result from previous research is that a male’s chance of homosexuality increases with the number of biological older brothers he has—even when he grows up away from his older male siblings (Blanchard and Bogaert). Scientists explain that, with each male fetus, a mother develops an increased immunization to an antigen produced by the male fetuses, and this antigen likely plays a role in masculinizing the brain.

These studies and others—while unable to point to a specific gene—do point to the idea that homosexuality may be inherited through a polymorphic gene, which is a gene that has more than one different form, and can exhibit either form. Studies have shown that this gene inheritance must be more complex than for common Mendelian traits.

To take the next step, Gavrilets and Rice have developed several mathematical models that make contrasting predictions for the possible factors responsible for the polymorphism of genes influencing homosexuality. Hopefully, the predictions generated by these models will guide future tests and help zone in on the correct genetic characteristics involved in sexual orientation. As Rice explains, past research has shown the complexity inherent in determining the cause(s) of homosexuality.

“We know that homosexuality (gay or lesbian) can be caused by simple genetic changes in fruit flies, and since so many reproductive and neurological genes are shared by flies and humans, it seems highly likely that there are major genes influencing homosexuality in humans,” said Rice. “However, we also have firm evidence for a birth-order effect on male homosexuality, and discordance in the expression of homosexuality of identical twins, so clearly there is also an environmental influence on the trait.”

Gavrilets and Rice identify two main factors that may explain the polymorphism of a gene (and how the gene spreads): overdominance and sexual antagonism. Overdominance refers to phenotypes that come from heterozygous genes, and the advantages promoting genetic variation. Sexual antagonistic traits are those that are advantageous in one sex, but may cause homosexuality in the other sex. For a variety of different gene inheritance patterns, the scientists provide mathematical models that require, in essence, that the benefits for one sex must outweigh the costs for the other sex.

In their study, Gavrilets and Rice make predictions for the likelihood of certain types of genes (e.g. autosomal or sex-linked, recessive or dominant, with small or large effects) favoring either overdominance or sexual antagonism under different conditions. However, many possibilities remain, and research into each one will determine how well they satisfy the requirements provided in this study.

“The research so far that I think is most illuminating on this topic are the studies showing that homosexuality can have a simple genetic foundation in fruit flies,” said Rice. “I think that it is too early to decide which of our models (or one yet to be formulated) is most feasible. However, based on the abundance of sexually antagonistic variation found in fruit flies, the sexually antagonistic variation seems like a probable candidate process leading to polymorphism for homosexuality.”

Citation: Gavrilets, Sergey and Rice, William R. “Genetic models of homosexuality: generating testable predictions.” Proceedings of the Royal Society B (2006) 273, 3031-3038.

By Lisa Zyga, Copyrght 2006 PhysOrg.com

Designer Babies Bad, Modified for "Morality" Babies Good?

Reverent Albert Mohler - Baptist Minister with a Congregation of 16 million believers.

In response to negative feedback to his comment that there is a "Biblical Justification for modifying babies "in eutero" to eliminate homosexual tendencies, due to the biblical definition of homosexuality as sinful". http://www.albertmohler.com/radio_show.php?cdate=2007-03-02


To my fellow evangelical Christians:

1. Let's get this straight -- God's condemnation of sin is not determined by science, but by God's Word. The Bible could not be more clear -- all forms of homosexual behavior are expressly condemned as sin. In so doing the Bible uses its strongest vocabulary and places this condemnation in the larger context of the Creator's rightful expectation of our stewardship of the sexual gift. All manifestations of homosexuality are thus representations of human sinfulness and rebellion against God's express will. Nothing can alter this fact, and no discovery in science or any other human endeavor can change God's verdict.

? Which version of the bible? The original Greek version that uses an oft mistranslated word for homosexuality? (the one referring to catamites, IIRC)

2. There is no conclusive research that indicates any biological basis for sexual orientation. But -- and this is a big "if" here -- if science were ever to discover a correlation or causation with biological factors, Christians should not be surprised. We believe in the catastrophic and comprehensive effects of the Fall and God's judgment upon sin.

? Way to remove self-determination from humanity as a species by attributing a mythical crime carried over to all individuals to the nth generation.

3. Such a discovery, if it were to be accepted, would not change God's condemnation of all forms of homosexual behavior, nor would it mean that this represents the inviolable "identity" of any individual. As I argued previously, moral responsibility does not require absolute moral choice. A soldier in battle may not have chosen to be in a situation of moral anguish, but he is still absolutely responsible for his decisions and actions. Those who commit homosexual acts, whoever they are and whatever their biological profile, are absolutely responsible for their sin. Regardless of any actual or hypothetical orientation, those who commit same-sex acts are responsible for the choice to commit the sinful act. Those who claim that they did not choose their sexual attraction are nevertheless fully responsible for choosing to perform sexual acts the Bible condemns as sin -- period.

? Yup. Typical church talk. Repress thy impulse to be sexual, for sex and sexuality is evil.

4. Some Christians seem absolutely convinced that there is no such thing as sexual orientation. There is a point to be made here. No "orientation" can alter the sinful status of sinful acts. Some have written me to say that there is no such reality as a homosexual, only those who perform homosexual acts. This flies in the face of the Bible, however, which speaks of those who commit such sins by their sin -- murderers, liars, adulterers, gossips, etc. It does not help to deny this. But, even though no "orientation" can alter the moral status of actions, the fact remains that some persons are sexually attracted to persons of the same sex while the majority are sexually attracted to persons of the opposite sex. There are other terms to use here, ranging from "sexual attraction pattern" to "sexual arousal profile," but sexual orientation seems a bit less explicit and is generally understood within the culture.

? Repress! Repress!

5. Research into the human genome and the possibility of germ-line therapies raises all kinds of moral concerns, ranging from the creation of designer babies to the redefinition of humanity. In one article, I was said to advocate genetic therapies. I never said that, and I resolutely oppose such proposals. I would not advocate the use of genetic therapies to create heterosexual babies -- or any other therapy of this type. The hypothetical question I addressed had nothing to do with genetic factors at all. Furthermore, genetic factors are likely to be so complex and inter-related that no single genetic factor or set of factors is likely to be found to cause anything as complex as sexual attraction.

? So what are you saying. Its ok to modify babies in eutero or its not ok to modify babies in eutero?

6. Caring Christians will be aware of the fact that many persons who struggle with homosexuality -- males and females -- testify as Christian believers or as those troubled in conscience that they simply have no idea where same-sex desire originated in their lives. They do know that they did not choose this pattern of attraction. Again, that does not reduce their moral responsibility in any way or to any degree. But caring Christians, fully committed to the sole authority of the Bible, must want to help persons to understand and deal with this specific temptation to sin.

? Like send them to the same rehab center that made Ted Haggard into a fully reformed, 100% Heterosexual Man despite years of homosexual dalliance?

7. The causes of same-sex attraction are likely to be very complex. The research of Joseph Nicolosi and others points to specific social and environmental factors as a prime cause. Boys who do not identify themselves with Dad by age two are clearly at risk. Dr. James Dobson addresses many of these factors in his book, Bringing Up Boys. Given the devastating impact of the Fall, we should not be shaken to our foundations if other causative factors are found. In any event, Christian compassion must lead us to want to know how this would happen in order that we can help those struggling with this sin. We should be thankful for those who, through biblical counsel and guidance, are helping homosexuals to find victory in Christ.

? Once more with the fall. An innocent 2 year old child who does not associate himself with Daddy should not be burdened by a mythical crime commited by mythical figureheads in a bronze age manual for faith that is grossly out of context for the 21 century.

8. Let's remember that all of us are born with a huge moral defect -- we are sinners from the start. Christians who have responded with claims that God would not allow a person to be born with a bent toward sin miss the clear biblical teaching that all of us are born with a bent toward sin and with a sin nature. We are born marked by Adam's sin and already under God's just condemnation for that sin.

? Humanity IS EVIL. Sinners all. Sorry I just can't buy that identity-crushing responsibility-destroying identity foisted onto an 'imperfect humanity'.

9. The only cure for sin itself is the cross of Christ. No therapy will cleanse us of sin, no treatment will atone. Only the shed blood of Jesus Christ will save, and salvation is found in Him alone.

? this just makes no sense at all.

10. Thanks are due to all who wrote or contacted me about these issues. That is not an easy thing to write, given the caustic tone of many communications and the fact that so many did not even bother to read my article. Nevertheless, I learned from your responses, and I am sure that God intended them for my good. I also want to be humble in asking fellow believers to join me in thinking about these crucial questions. If I have missed something, point it out. If I have violated Scripture in any way, bring this to my attention. If I am confused in any way, point to clarification.

? Clarification: you are basing your moral stand on a mis-translated moral story that requires the assumption of an invisible sky being that wants us to be happy, but has spitefully invested us as a species with (from your mythology) a lingering taint of evil sinfulness that was produced by a mythical figurehead deep in the distant past failing to follow instructions, thus condemning us all to roast in an eternal BBQ in celebration of the omni-benevolent sky-beings spite.
Are you confused? Indubitably.